FreeCAD: free parametric CAD for 3D printing

What FreeCAD offers

FreeCAD is open source CAD with no fees and no restrictions on commercial use. It is parametric, so changing one dimension recalculates the model. It has workbenches for sketches, solids, assemblies and drawings. You will find more on Wikipedia.

It is stricter and slower to learn than commercial programs. In return you get a program that nobody can switch off or make more expensive.

Exporting from FreeCAD

Select the body and via File, Export choose STL, 3MF or STEP. For STL you set the accuracy on export, that is the mesh deviation. For round shapes use a lower value, otherwise the print will be visibly faceted.

Common mistakes

• Several bodies in one file. Export only what you want printed, otherwise everything gets printed.
• A mesh that is too coarse. Cylinders look like polygons because the export had a large tolerance.
• Thin walls. Walls under 0.8 mm may not come out cleanly.

FreeCAD and your order

FreeCAD is chosen by people who want full parametric CAD without licence restrictions, or who want certainty that their files can still be opened in ten years. It suits boxes, holders, gear parts and spare parts with set dimensions. With large assemblies it tends to be slower than commercial programs. For very organic shapes reach for Blender instead.

You upload the exported file to the calculator. After upload you see the model, its dimensions and a price based on the actual material use and time. If the part belongs to an assembly, think about the tolerances and the direction it will be printed in, because strength depends on it. There is more in the entry on model orientation.